Regolith is a layer of loose, heterogeneous material covering solid rock. The term is a combination of two Greek words: rhegos (ῥῆγος), "blanket", and lithos (λίθος), "rock". It includes dust, soil, broken rock, and other related materials and is present on Earth, the Moon, some asteroids, and other planets. The term was first defined by George P. Merrill in 1897 who stated, "In places this covering is made up of material originating through ro… (More on Regolith)